Fix Universal Credit claimant and qualifying-child roles

changelog.d/uc-claimant-relationships.added.md

@@ -0,0 +1 @@
+- Added the is_uc_claimant input to identify Universal Credit claimants and partners from recorded benefit-unit relationships.

changelog.d/uc-claimant-relationships.fixed.md

@@ -0,0 +1 @@
+- Fixed Universal Credit claimant classification and work allowances for families with qualifying young people, and excluded claimants from their own ordinary and disability child elements and two-child-limit counts.

policyengine_uk/tests/policy/baseline/finance/benefit/child_qualifying_young_person.yaml

@@ -175,6 +175,7 @@
     people:
       parent:
         age: 40
+        is_parent: true
       looked_after_child:
         age: 12
         is_looked_after_by_local_authority: true

policyengine_uk/tests/policy/baseline/finance/benefit/family/universal_credit/child_element/disability/uc_individual_disabled_child_element.yaml

@@ -3,6 +3,19 @@
   absolute_error_margin: 100
   input:
     age: 6
+    is_uc_claimant: false
     is_disabled_for_benefits: true
   output:
     uc_individual_disabled_child_element: 1_902
+
+- name: Case 2, an explicit young claimant receives no disabled child addition for themselves.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    age: 18
+    is_in_non_advanced_education: true
+    is_uc_claimant: true
+    is_disabled_for_benefits: true
+  output:
+    is_child_or_qualifying_young_person_for_universal_credit: true
+    uc_individual_disabled_child_element: 0

policyengine_uk/tests/policy/baseline/finance/benefit/family/universal_credit/child_element/disability/uc_individual_severely_disabled_child_element.yaml

@@ -3,6 +3,18 @@
   absolute_error_margin: 100
   input:
     age: 6
+    is_uc_claimant: false
     is_severely_disabled_for_benefits: true
   output:
     uc_individual_severely_disabled_child_element: 5_942
+
+- name: Case 2, a fallback young claimant receives no severe child addition for themselves.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    age: 18
+    is_in_non_advanced_education: true
+    is_severely_disabled_for_benefits: true
+  output:
+    is_uc_claimant: true
+    uc_individual_severely_disabled_child_element: 0

policyengine_uk/tests/policy/baseline/finance/benefit/family/universal_credit/claimant_child_element.yaml

@@ -0,0 +1,132 @@
+# The UC child element is for a claimant's dependent child, not the claimant.
+# In 2025 the under-25 single allowance is 316.98 * 12 = 3,803.76;
+# the amount per child born after April 2017 is 292.81 * 12 = 3,513.72.
+
+- name: Case 1, an explicitly identified young claimant is not their own child.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 18
+        is_in_non_advanced_education: true
+        is_uc_claimant: true
+    benunits:
+      benunit:
+        members: [person1]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1]
+  output:
+    # The age/education predicate remains unchanged; claim roles exclude it
+    # from UC child amounts without redefining qualification for other uses.
+    is_child_or_qualifying_young_person_for_universal_credit: true
+    uc_child_index: -1
+    uc_individual_child_element: 0
+    uc_is_child_limit_affected: false
+    uc_work_allowance: 0
+    universal_credit: 3_803.76
+
+# No is_uc_claimant input: evaluating final UC and child ordering exercises
+# the fallback through the QYP predicate and detects any dependency cycle.
+- name: Case 2, a young parent inferred from source roles receives one child element.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 18
+        is_benunit_head: true
+        is_parent: true
+        is_in_non_advanced_education: true
+      person2:
+        age: 1
+        is_benunit_head: false
+    benunits:
+      benunit:
+        members: [person1, person2]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2]
+  output:
+    is_uc_claimant: [true, false]
+    uc_child_index: [-1, 1]
+    uc_individual_child_element: [0, 3_513.72]
+    uc_is_child_limit_affected: [false, false]
+    uc_work_allowance: 8_208
+    universal_credit: 7_317.48
+
+- name: Case 3, a young claimant does not use a place under the two-child limit.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 18
+        is_benunit_head: true
+        is_parent: true
+        is_in_non_advanced_education: true
+      person2:
+        age: 3
+        is_benunit_head: false
+      person3:
+        age: 2
+        is_benunit_head: false
+      person4:
+        age: 1
+        is_benunit_head: false
+    benunits:
+      benunit:
+        members: [person1, person2, person3, person4]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2, person3, person4]
+  output:
+    is_uc_claimant: [true, false, false, false]
+    uc_child_index: [-1, 1, 2, 3]
+    uc_individual_child_element: [0, 3_513.72, 3_513.72, 0]
+    uc_is_child_limit_affected: [false, false, false, true]
+    uc_child_element: 7_027.44
+    universal_credit: 10_831.20
+
+- name: Case 4, disabled dependent additions remain payable beyond the ordinary child limit.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_parent: true
+      person2:
+        age: 7
+      person3:
+        age: 6
+      person4:
+        age: 4
+        is_disabled_for_benefits: true
+      person5:
+        age: 2
+        is_severely_disabled_for_benefits: true
+    benunits:
+      benunit:
+        members: [person1, person2, person3, person4, person5]
+        uc_LCWRA_element: 0
+  output:
+    # Reg. 24(2) disabled-child additions are separate from the ordinary limit.
+    # 2025 monthly additions: 158.76 * 12 = 1,905.12; 495.87 * 12 = 5,950.44.
+    is_uc_claimant: [true, false, false, false, false]
+    uc_child_index: [-1, 1, 2, 3, 4]
+    uc_individual_child_element: [0, 3_513.72, 3_513.72, 0, 0]
+    uc_is_child_limit_affected: [false, false, false, true, true]
+    uc_individual_disabled_child_element: [0, 0, 0, 1_905.12, 0]
+    uc_individual_severely_disabled_child_element: [0, 0, 0, 0, 5_950.44]
+    uc_disability_elements: 7_855.56

policyengine_uk/tests/policy/baseline/finance/benefit/family/universal_credit/claimant_relationships.yaml

@@ -0,0 +1,215 @@
+# Regulations 22 and 36 of SI 2013/376 distinguish claimants from the
+# children or qualifying young people for whom they are responsible.
+# 2025 annual amounts: single 25+ = 400.14 * 12; couple under 25 =
+# 497.55 * 12; first child born before April 2017 = 339 * 12.
+# With no housing, the work allowance is 684 * 12. On 12,000 earnings
+# below the tax/NI thresholds, the UC reduction is (12,000 - 8,208) * 0.55.
+
+- name: Case 1, lone parent with an 18-year-old qualifying young person.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        employment_income: 12_000
+        is_benunit_head: true
+        is_parent: true
+      person2:
+        age: 18
+        is_benunit_head: false
+        is_in_non_advanced_education: true
+    benunits:
+      benunit:
+        members: [person1, person2]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2]
+  output:
+    uc_standard_allowance_claimant_type: SINGLE_OLD
+    uc_standard_allowance: 4_801.68
+    uc_work_allowance: 8_208
+    uc_child_element: 4_068
+    universal_credit: 6_784.08
+
+- name: Case 2, lone parent with a 19-year-old before the qualifying terminal date.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        employment_income: 12_000
+        is_benunit_head: true
+        is_parent: true
+      person2:
+        age: 19
+        is_benunit_head: false
+        is_in_non_advanced_education: true
+        age_started_or_accepted_current_education_or_training: 18
+        is_before_universal_credit_qualifying_young_person_terminal_date: true
+    benunits:
+      benunit:
+        members: [person1, person2]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2]
+  output:
+    uc_standard_allowance_claimant_type: SINGLE_OLD
+    uc_standard_allowance: 4_801.68
+    uc_work_allowance: 8_208
+    uc_child_element: 4_068
+    universal_credit: 6_784.08
+
+- name: Case 3, genuine couple with an older qualifying child remains a couple.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        employment_income: 12_000
+        is_benunit_head: true
+        is_parent: true
+      person2:
+        age: 39
+        is_benunit_head: false
+        is_parent: true
+      person3:
+        age: 18
+        is_benunit_head: false
+        is_in_non_advanced_education: true
+    benunits:
+      benunit:
+        members: [person1, person2, person3]
+        is_married: false
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2, person3]
+  output:
+    uc_standard_allowance_claimant_type: COUPLE_OLD
+    uc_standard_allowance: 7_537.20
+    uc_work_allowance: 8_208
+    universal_credit: 9_519.60
+
+- name: Case 4, cohabiting young claimants do not need a marriage input.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 24
+      person2:
+        age: 23
+    benunits:
+      benunit:
+        members: [person1, person2]
+        is_married: false
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2]
+  output:
+    uc_standard_allowance_claimant_type: COUPLE_YOUNG
+    uc_standard_allowance: 5_970.60
+    uc_work_allowance: 0
+    universal_credit: 5_970.60
+
+# The existing eligibility formula excludes all under-18 claimants. This case
+# fixes claimant classification only; it does not implement the legal exceptions.
+- name: Case 5, an under-18 parent is not a couple because adult count is zero.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 17
+        is_benunit_head: true
+        is_parent: true
+      person2:
+        age: 1
+        is_benunit_head: false
+    benunits:
+      benunit:
+        members: [person1, person2]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+    households:
+      household:
+        members: [person1, person2]
+  output:
+    uc_standard_allowance_claimant_type: SINGLE_YOUNG
+    uc_standard_allowance: 3_803.76
+    universal_credit: 0
+
+- name: Case 6, retained nonqualifying child roles do not imply a partner.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_uc_claimant: true
+      person2:
+        age: 19
+        is_uc_claimant: false
+    benunits:
+      benunit:
+        members: [person1, person2]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2]
+  output:
+    # The generic family variable deliberately retains its existing semantics.
+    family_type: COUPLE_NO_CHILDREN
+    uc_standard_allowance_claimant_type: SINGLE_OLD
+    uc_standard_allowance: 4_801.68
+    uc_work_allowance: 0
+    uc_child_element: 0
+    universal_credit: 4_801.68
+
+- name: Case 7, a cohabiting 19-year-old in education is not the partner's child.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 24
+      person2:
+        age: 19
+        is_in_non_advanced_education: true
+        age_started_or_accepted_current_education_or_training: 18
+        is_before_universal_credit_qualifying_young_person_terminal_date: true
+    benunits:
+      benunit:
+        members: [person1, person2]
+        uc_reported_capital: 0
+        uc_latent_deduction_rate: 0
+        benefit_cap_reduction: 0
+    households:
+      household:
+        members: [person1, person2]
+  output:
+    # No role or marriage inputs: two claimants under 25, no dependent children.
+    # The 2025 monthly couple allowance is 497.55; 497.55 * 12 = 5,970.60.
+    is_uc_claimant: [true, true]
+    uc_standard_allowance_claimant_type: COUPLE_YOUNG
+    uc_standard_allowance: 5_970.60
+    uc_child_index: [-1, -1]
+    uc_child_element: 0
+    uc_work_allowance: 0
+    universal_credit: 5_970.60